The present disclosure relates to a display input device including a display unit and a touch panel.
For instance, a display input device for inputting various settings via a screen may be attached to an apparatus or equipment. Further, as to a mobile phone terminal or the like, the number of hardware keys that can be disposed thereon is limited. Therefore, a plurality of roles (meanings) may be assigned to one key. Therefore, an input error may be caused because a user does not know a role (process) assigned to the current state of a key. In order to prevent such a decrease of operability, the following techniques are known.
Specifically, there is known an input device including an input unit for inputting a press of a key as an execution instruction of a process assigned to the key, a long press detection unit for detecting a long press state in which a key is continuously pressed, and an informing unit for informing a user of a process assigned to the key while inhibiting the input by the input unit when the long press state of the key is detected. With this structure, it is aimed to enable the user to easily check a process assigned to each key.
An image forming apparatus such as a copier, a multifunction peripheral, a printer, or a FAX apparatus may also be equipped with a display input device (which may referred to also as an “operation panel”). The operation panel of the image forming apparatus displays a screen for selecting a set item or for setting a set value. Because there are many selectable set items and settable set values, there are prepared many types of screens.
First, a highest layer screen in a hierarchical structure is displayed on the operation panel. Further, a button (key) for selecting a set item (classification or category) is operated on the screen (a display position thereof is touched). As a result, a next layer (one lower layer) screen is displayed. In the case of further necessity, a button is operated for selecting one of set items in a lower layer of the selected set item. Such button selection is repeated until reaching a desired screen. In other words, in order to reach a desired screen, operations on buttons are repeated so as to trace an appropriate path to a lower layer screen one by one. In this way, displays on the operation panel have a hierarchical structure (or a tree structure).
In order to switch a display screen, it is necessary to actually operate a button in a screen. In other words, a screen display cannot be switched unless a display position of a button is touched. Therefore, in order or check a lower screen by a plurality of layers, it is necessary to actually operate buttons a plurality of times (the number of layers to move), so as to switch screens. Therefore, there is a problem that it is difficult to easily check screens in lower layers. In particular, a screen in a lower layer of the current layer screen by two or more layers cannot be checked by one operation. In addition, an operation to return to the original screen is necessary unless the screen after switching is a desired screen. Therefore, a long time and operation may be necessary in many cases in order to reach a desired screen so as to set a set value.
In addition, in order to complete setting of one set value, it may be necessary to move down layers by two or more layers in many cases (e.g., in setting about the system). Therefore, transition of screens (switching of screens to a lower layer) is repeated. There may be a case where because a target screen is in a deep layer, the path to the desired screen cannot be found, and transition to an incorrect screen and operation for returning to the original screen are repeated. In this case, the number of operation times becomes very large, and the operation is complicated. In addition, because of repetition of screen switching and returning operation, the current position may become unknown.
Here, the known mobile phone terminal described above displays a function (process) assigned to a long-pressed key. However, though the function is displayed, the content of the screen cannot be checked unless the button is actually pressed. In addition, in order to move between layers of the display screen, it is necessary to operate the button every time. It is not able to check a screen by one operation when the screen is apart by a plurality of layers. In addition, the current layer may become unknown by repeating pressing of an incorrect key and the returning operation afterward.